github.com/mccv1r0/cni@v0.7.0-alpha1/cnitool/cnitool.go (about)

     1  // Copyright 2015 CNI authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package main
    16  
    17  import (
    18  	"crypto/sha512"
    19  	"encoding/json"
    20  	"fmt"
    21  	"os"
    22  	"path/filepath"
    23  	"strings"
    24  
    25  	"github.com/containernetworking/cni/libcni"
    26  )
    27  
    28  const (
    29  	EnvCNIPath        = "CNI_PATH"
    30  	EnvNetDir         = "NETCONFPATH"
    31  	EnvCapabilityArgs = "CAP_ARGS"
    32  	EnvCNIArgs        = "CNI_ARGS"
    33  
    34  	DefaultNetDir = "/etc/cni/net.d"
    35  
    36  	CmdAdd = "add"
    37  	CmdDel = "del"
    38  )
    39  
    40  func parseArgs(args string) ([][2]string, error) {
    41  	var result [][2]string
    42  
    43  	pairs := strings.Split(args, ";")
    44  	for _, pair := range pairs {
    45  		kv := strings.Split(pair, "=")
    46  		if len(kv) != 2 || kv[0] == "" || kv[1] == "" {
    47  			return nil, fmt.Errorf("invalid CNI_ARGS pair %q", pair)
    48  		}
    49  
    50  		result = append(result, [2]string{kv[0], kv[1]})
    51  	}
    52  
    53  	return result, nil
    54  }
    55  
    56  func main() {
    57  	if len(os.Args) < 3 {
    58  		usage()
    59  		return
    60  	}
    61  
    62  	netdir := os.Getenv(EnvNetDir)
    63  	if netdir == "" {
    64  		netdir = DefaultNetDir
    65  	}
    66  	netconf, err := libcni.LoadConfList(netdir, os.Args[2])
    67  	if err != nil {
    68  		exit(err)
    69  	}
    70  
    71  	var capabilityArgs map[string]interface{}
    72  	capabilityArgsValue := os.Getenv(EnvCapabilityArgs)
    73  	if len(capabilityArgsValue) > 0 {
    74  		if err = json.Unmarshal([]byte(capabilityArgsValue), &capabilityArgs); err != nil {
    75  			exit(err)
    76  		}
    77  	}
    78  
    79  	var cniArgs [][2]string
    80  	args := os.Getenv(EnvCNIArgs)
    81  	if len(args) > 0 {
    82  		cniArgs, err = parseArgs(args)
    83  		if err != nil {
    84  			exit(err)
    85  		}
    86  	}
    87  
    88  	netns := os.Args[3]
    89  	netns, err = filepath.Abs(netns)
    90  	if err != nil {
    91  		exit(err)
    92  	}
    93  
    94  	// Generate the containerid by hashing the netns path
    95  	s := sha512.Sum512([]byte(netns))
    96  	containerID := fmt.Sprintf("cnitool-%x", s[:10])
    97  
    98  	cninet := libcni.NewCNIConfig(filepath.SplitList(os.Getenv(EnvCNIPath)), nil)
    99  
   100  	rt := &libcni.RuntimeConf{
   101  		ContainerID:    containerID,
   102  		NetNS:          netns,
   103  		IfName:         "eth0",
   104  		Args:           cniArgs,
   105  		CapabilityArgs: capabilityArgs,
   106  	}
   107  
   108  	switch os.Args[1] {
   109  	case CmdAdd:
   110  		result, err := cninet.AddNetworkList(netconf, rt)
   111  		if result != nil {
   112  			_ = result.Print()
   113  		}
   114  		exit(err)
   115  	case CmdDel:
   116  		exit(cninet.DelNetworkList(netconf, rt))
   117  	}
   118  }
   119  
   120  func usage() {
   121  	exe := filepath.Base(os.Args[0])
   122  
   123  	fmt.Fprintf(os.Stderr, "%s: Add or remove network interfaces from a network namespace\n", exe)
   124  	fmt.Fprintf(os.Stderr, "  %s %s <net> <netns>\n", exe, CmdAdd)
   125  	fmt.Fprintf(os.Stderr, "  %s %s <net> <netns>\n", exe, CmdDel)
   126  	os.Exit(1)
   127  }
   128  
   129  func exit(err error) {
   130  	if err != nil {
   131  		fmt.Fprintf(os.Stderr, "%s\n", err)
   132  		os.Exit(1)
   133  	}
   134  	os.Exit(0)
   135  }